Semiconductor devices are usually formed or arranged on a same substrate before they enter the packaging stage. The packaging stage includes several steps that are mainly designed to form several individual semiconductor assemblies. Singulation is one of the steps adopted to separate the semiconductor devices on the same substrate into several independent units.
Singulation may occur at different stages in semiconductor manufacturing. A semiconductor substrate may be singulated into individual dies after all of the semiconductor devices and interconnects are formed. The individual dies may be packaged separately to another semiconductor substrate that is then singulated again into a packaged chip. In some semiconductor manufacturing processes commonly referred to as the wafer-level packaging, a semiconductor substrate having all of the semiconductor devices and interconnects is packaged first to another substrate before singulation. Thus singulation may occur once or more times during semiconductor manufacturing.
In some approaches, the semiconductor substrate is placed on a tooling and fixed to the top surface of the tooling during the singulation process. A saw or other cutting device then separates the individual units along scribe lines. Because a small deviation from the scribe lines may remove device portions of the individual units and render the product defective, the singulation tooling would stop or not start if the semiconductor substrate is not firmly fixed to the top surface. Improved apparatus and method for a singulation process continue to be sought.